1. Field of the Invention
The present invention relates to a fluid filtering system. More particularly, the present invention relates to a modular filter cartridge which can be arranged into filter assemblies of various configurations by hydraulically and mechanically interconnecting a plurality of individual filter cartridges.
2. Description of the Related Art
The use of fluid filtering systems continues to expand into an ever increasing number of areas. For example, fluid filtering systems are used in research, medical, commercial, industrial, and even residential applications to treat fluids conventionally associated with such facilities. In particular, the treatment of water is one area in which the need for improved filtering systems continues to grow as the demand increases for cleaner, more pure water in homes as well as research laboratories, and the quality of municipal water supplies continues to deteriorate in many regions throughout the world. In addition to water, other fluids such as oil, bodily fluids, and the like also require treatment in many instances to remove unwanted contaminants, odors, bacteria, and the like.
The sequential treatment of fluids through multiple filters is known to have an affect on the quality of the filtered fluid as it passes through a filtering system. Both the number of filters and the type of filter media contained in the filters can affect the amount and type of contaminants removed from a treated fluid. Accordingly, it is desirable to provide a filtering system in which the number of individual filter cartridges, the type of filter media and the particular configuration of the filtering system can be readily assembled.
Filtering systems are known which include individual filter cartridges that are hydraulically connected to each other to form a filtering system. However, many of these filtering systems suffer from a variety of disadvantages. For example, many modular filtering systems hydraulically interconnect individual filter cartridges using threaded hydraulic fittings and tubing. In addition to providing the hydraulic circuit, the fittings and tubing may also provide the only mechanical support between the individual filter cartridges. Such systems are more prone to fluid leaks due to internal pressure or external forces placed on the filtering system. Furthermore, in such systems, modification of the particular filtering configuration or replacement of individual filter cartridges can be difficult, labor intensive tasks. An example of a filtering system using hydraulic fittings is disclosed by Dalessandro, in U.S. Pat. No. 4,786,420.
In an effort to overcome some of the foregoing disadvantages, filtering systems have been developed that eliminate such hydraulic fittings and tubing by using a fluid manifold that interconnects the individual filter cartridges. In general, the manifold of these systems is formed with fluid passages that hydraulically connect the filter cartridges in a desired configuration. However, such manifolds are typically made for a particular application and cannot be reconfigured once the internal flow passages are formed. Examples of filtering systems using manifolds are disclosed by Clack et al., in U.S. Pat. No. 5,128,035, and Slovak et al., in U.S. Pat. No. 5,143,601.
Another example of a water filter apparatus using multiple filter tubes in a sequential arrangement is disclosed by Gaignet, in U.S. Pat. No. 4,944,875. The apparatus includes a plurality of filter tubes which are connected both structurally and hydraulically by two molded end plates. The desired flow path is established by modifying the end plates prior to assembly to provide appropriate holes through internal partitions. The end plates are then permanently bonded to the ends of the tubes either thermally or adhesively. A major disadvantage of this apparatus is the inability to reconfigure the apparatus or replace filter tubes once the end plates are bonded to the tubes.
Accordingly, it is desirable to provide a fluid filtering system that includes a plurality of modular filter cartridges that can be readily connected and disconnected from each other to form a fluid circuit in a desired configuration.